Water pumps for marine engines generally include a flexible impeller mounted on a shaft in a pump housing for rotation therein. The flexible impeller must be removed annually when winterizing the marine engine to prevent the rubber from being damaged due to freezing and thawing. Because a marine engine is commonly operated in salt water, the impeller may become encrusted with silt and salt. It is common to have to replace the pump impeller after every 100 hours of operation.
In conventional marine engines, the water pump is mounted in an area dark and difficult to access. To change the flexible impeller, a cover plate must be removed. Known cover plates are screwed into the pump housing. Therefore, one must use a screw driver to remove the screws holding on a cover plate before changing the flexible impeller. Due to the location of the water pump, fitting a screw driver into a tight, dark area is challenging. Once the cover plate is removed, the flexible impeller must be removed from inside the pump housing.
One method of removing the flexible impeller is to use two sets of pliers. Two impeller blades are gripped on either side using the pliers. Alternatively, a screw driver may be used to pry an impeller from inside the pump housing.
For large impellers or impellers stuck on a shaft inside the pump housing, the methods described above may not be adequate. In such situations, the user may have to remove the water pump from the marine engine and work on removing the impeller remotely which may not be practical such as when a marine engine is being used at sea. Alternatively, a separate tool such as one disclosed in U.S. Pat. No. 6,394,753 or 8,312,607 may be used. However, it is unlikely such a separate tool is carried aboard the vessel driven by the marine engine with a failed water pump.
Accordingly, there is a need for a water pump for use in a marine engine with a tool for removing an impeller from inside the water pump.